Polyhydroxypregnane glycosides from Oxystelma esculentum var. alpini.

Three new polyhydroxypregnane glycosides named alpinoside A [kidjolanin 3-O-beta-d-glucopyranosyl-(1-->4)-beta-d-glucopyranosyl-(1-->4)-beta-d-thevetopyranosyl-(1-->4)-beta-d-cymaropyranosyl-(1-->4)-beta-d-cymaropyranoside], alpinoside B [kidjolanin 3-O-beta-d-glucopyranosyl-(1-->4)-beta-d-thevetopyranosyl-(1-->4)-beta-d-cymaropyranosyl-(1-->4)-beta-d-cymaropyranoside], and alpinoside C [kidjolanin 3-O-beta-d-glucopyranosyl-(1-->4)-beta-d-glucopyranosyl-(1-->4)-beta-d-oleandropyranosyl-(1-->4)-beta-d-cymaropyranosyl-(1-->4)-beta-d-cymaropyranoside] were isolated from the leaves of Oxystelma esculentum var. alpini. The structure elucidation was accomplished by extensive spectroscopic analysis and acid-catalyzed hydrolysis.